Influence of low-frequency modulation of welding current is investigational on descriptions of metal of guy-sutures at a hand arc/w on the currents of arc to 70 Amp. It is set that frequency of impulses of current within the limits of 10… 30 Hertzs at porosity 1,5…2 provides the increase of depth of melted of parent metal with the decline of grittiness of weld metal.